The invention relates to a preparation process of a live
bacillus thuringiensis preparation. The preparation process comprises the steps that
bacillus thuringiensis is inoculated into a
fermentation medium to be cultured after being subjected to primary and secondary seed enlarge culture; the quantity and conversion rate of bacillus are increased through fed-batch of a
carbon source in the
fermentation process, thus obviously increasing the unit yield and reducing the
unit cost; after
fermentation is completed, the fermentation liquor is concentrated by using a vacuum film
concentrator and the soluble synergistic substances, growth-stimulated substances and bacteriostatic active substances in the fermentation liquor can be effectively recovered; the concentrated fermentation liquor is dried and granulated by multistage low temperature spray fluidized
drying equipment, the granules are sorted and the
fine powder is trapped by a
cyclone separator and returns to be re-granulated, thus obtaining the
bacillus thuringiensis product, wherein, through biological
assay, the activity of each
gram of the bacillus thuringiensis
powder on cotton bollworms is not lower than 80000IU / mg and the content of
insecticidal crystal proteins in the product is not lower than 13%; the
tail gas is treated and is discharged up to the standard. The preparation process has the advantages that the active substances in the fermentation liquor can be furthest retained; the product quality and the equipment
utilization rate are high; the
biological activity is better maintained; the
waste gas and the
wastewater are discharged up to the standard; the preparation process can be used for large-scale industrial production.